The roof and house will impede and block reception.
Get the VU-190XR Above the Roof.
The VU-190XR Must Be UP HIGH In The Air so as to have the best shot at reception.
If the VU-190XR is in good condition , not broken or corroded.
Replace the matching transformer (balun) that connects the antenna to the coax with a New Matching Transformer.
And connect a NEW Continues Length of Coax to the matching transformer and run the NEW Continues Length of Coax Direct to 1 Tv.
Aim the VU-190XR at about 224 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Digital Tv Tuners can develop - Digital Glitches - that are not cleared out with simple channel scans.
Do a Double Rescan ,
http://www.dtv.gov/rescan.html.
As always , trees and tree leaves , plants and plant leaves , have Negative effect on Broadcast Tv Reception and so do buildings including your own roof and house and other obstructions.
The Best Practice is to place the VU-190XR antenna at a location that has the least amount to no amount of obstructions of any type or kind in the directions of reception.
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